Design and application of high-strength dissolvable bridge plug

During the staged fracturing for shale gas exploitation, composite bridge plug is needed for plugging and coiled tubing is needed in the later period for drilling and milling, so it faces the problems of long construction cycle, high cost and great risk. In order to reduce shale gas exploitation cost and improve the construction effect, this paper developed dissolvable bridge plug, which adopts the high-strength degradable materials to realize reliable setting and complete and effective dissolution. Setting release test, pressure bearing test and dissolubility test were carried out on dissolvable bridge plug in laboratories. It is shown that the dissolvable bridge plug can satisfy the field construction requirements in all indicators. By the end of December 2019, dissolvable bridge plug had been practically applied in 28 intervals in total. And the field application results indicate that dissolvable bridge plug has the advantages of stable property and safe and reliable setting and can be dissolved completely after the fracturing, without plugging the blowout and gas production channels.